The majority of metal beverage cans in the marketplace today are two-piece cans, comprising a one-piece can body with a can end seamed to the open end.
Furthermore, the most common type of can end is that known as the “stay on tab” end. A stay on tab end comprises a tab that is levered up by the consumer's finger to cause a fracture along a score line defining the aperture. Once opened, the tab is pressed back against the end and remains attached to the can end. A can end of this type has been produced for some years by Crown Holdings Inc under the brand name SuperEnd®.
For some applications it is desirable to increase the liquid flow rate through the aperture of a can end. For example, in restaurants and cafes it may be helpful to quickly empty the contents of a can into a drinking glass. Consumers drinking directly from the can may also find this beneficial. Can ends that avoid so-called “glugging” during pouring can also be desirable.
Crown Holdings Inc addressed these problem with a can end known by the brand name 360 End®. The 360 End is an end suitable for closing a can body with an opening having an inside diameter of around 52 mm (otherwise known as a 202 diameter neck where 202 nominally represents 2 2/16″ over the seam when the can has been seamed) and allows almost the entire centre panel of the end to be removed when opened. Crown has also produced an end known by the brand name Global Vent™ and which features a dual aperture opening mechanism to facilitate a smoother pour from the beverage can, enhancing the consumer experience. Consumers simply open the beverage can as usual, turn the tab to align it over a button-shaped depression to the right of the main opening, and then press down to activate the second aperture. The second aperture provides a venting hole allowing air to flow into the can as the product flows out of the main aperture. Whilst the Global Vent™ end provides extremely good performance it requires an additional opening step as compared with conventional ends.
In addition to these Crown Holdings Inc can ends, other manufacturers have marketed or attempted to market can ends that claim to facilitate an increased flow rate and/or anti-glugging.
Whilst at first sight it might seem obvious to increase the size and/or shape of the aperture to increase flow rate and avoid glugging, this is far from trivial. Any practical design must maintain both the ease of opening of conventional ends and maintain the level of pressure performance. Additionally, in a very competitive field, any new can end designs should not add significantly to production costs.
US20150329238 is concerned with beverage can ends with a supplemental venting feature.